What should I consider before starting a custom home project?

So, I’m kinda stressing about this whole custom home thing. My friend recently finished hers, and it was a disaster. The builder completely ignored what she wanted in the design, and the whole project took way longer than planned. She kept getting pushed aside and wasn’t even updated on what was happening. I don’t want to end up in the same boat. Like, how do I make sure I’m not just another customer to them, but actually heard?